Last recorded file-tree snapshot (NOT a live check)

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already mark the call read-only and idempotent; the description adds the crucial behavioral caveat that the result may be stale and that running this tool does not execute rrt tree --check. This is exactly the kind of beyond-schema context the dimension asks for, and it contradicts nothing.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three short sentences front-load the core purpose and limitation, then give the alternative paths. No sentence is redundant; even the direct-read equivalent earns its place by giving agents a cheaper option.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a zero-parameter, read-only tool with an output schema, the description covers the data source, the staleness limitation, the absence of a live check, and fallback alternatives. Nothing an agent needs in order to invoke or interpret this tool is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool has zero parameters and schema coverage is vacuously complete, so there are no parameter semantics to document. The rubric's baseline for a zero-parameter tool is 4, and the description does not need to compensate for any missing schema detail.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific verb ('Return') and resource (the repository tree snapshot from .rrt/tree.lock.toml), and the title/description explicitly frames it as the last recorded snapshot rather than a live check. This prevents confusion with any current-state tree tool, even without naming a sibling.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It explicitly says when not to use the tool (when you need to know whether the working tree still matches) and gives the alternative: use the CLI because no MCP tool provides that check. It also offers the direct-file-read equivalent, so an agent has clear routing guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.